Abstract

Over 30% of Alaska is subject to snow avalanche activity. Steep slopes and heavy snowfall combine to cause avalanches that become a hazard as remote mountain areas are used and developed. While mapping of individual slopes in remote areas that might be hazardous to backcountry travellers is prohibitively general, mapping of areas which are or are likely to be developed is necessary for the safe location of permanent structures. Because settlement in mountainous areas of Alaska is relatively recent, very little data is available on rare, very large avalanche events of the type likely to destroy property. Indirect evidence of past events can be gleaned from knowledge of snowpack characteristics, avalanche dynamics, and analysis of terrain, but little work has been done to date in Alaska and less published. Once mapping has been completed, mitigation of avalanche hazards can be accomplished through avalanche zoning or sometimes engineering.